1. Field of the Invention
This invention relates to coating compositions based upon noncarbonated complexes of calcium and magnesium oxide.
2. Description of the Prior Art
Compositions based upon high stoichiometric excesses of magnesium carbonates including alkylbenzene sulfonic acids are well known. Illustrative of such compositions are those disclosed in U.S. Pat. Nos. 3,242,079; 3,372,115; 3,865,737 and British Pat. No. 1,570,909. Additionally, noncarbonated magnesium-containing complexes for coating compositions and oil additives are disclosed in U.S. Pat. No. 4,094,801.
The compounds taught in U.S. Pat. No. 4,094,801 are based upon specific molar ratios of magnesium oxide, oleophilic acids including sulfonic acids, and water. More particularly, these compositions are combined with other hydrophobic compounds such as waxes, along with polymeric materials and the like and deemed useful as anticorrosion compositions. This U.S. patent teaches that it is necessary to have a molar ratio of about 0.7:1 to 3:1 water to magnesium oxide, and in the preparation of coating compositions, molar ratios of 1:1 and 3:1 are most desirable.
In accordance with the present invention, compositions containing predominantly magnesium oxide can be prepared which have excellent salt spray resistance, rendering them particularly useful for anticorrosion coating compositions. Additionally, in accordance with the present invention, coating compositions have been prepared utilizing oxides other than magnesium oxide, which have excellent anticorrosion properties.